Make like a snake

In March 2021 I wrote a blog about very decorative caterpillars which turned out the larvae of Golden Notodontid Moths (Neola semiaurata) that I found munching down on the Black Wattles around the dam. The caterpillars themselves are fantastical to look at sporting many colours and imaginative plumes but what I didn’t realise at the time was their response to disturbance. When disturbed a bright red outgrowth called an osmeterium erupts from the throat and eye spots are displayed on the rear. I promised to give the caterpillar a tickle if I ever saw it again to check out these defensive strategies.

Moving on two years and the same Black Wattles are hosting the same caterpillars. Rather than ‘give it a tickle’ I could only go as far as slightly shaking the branch it was feeding on. It immediately went into its defensive posture (pictured above) that doesn’t look so scary when viewed from the side but when viewed from behind presents a far more daunting picture.

When disturbed the caterpillar arches its back over its body, squeezes its two rear ‘false legs’ together and reveals two large eye spots. Viewed from the rear it looks all-the-world like a small viper (pictured left). If I was a predator I’d be convinced to stay away.

As for the osmeterium – a more vigourous shake of the branch is obviously required.